1. Field of the Invention
The present invention relates to a load port for loading into a semiconductor manufacturing apparatus a clean box whose interior is kept clean in a local clean space system that is to be installed in the semiconductor manufacturing apparatus, and more particularly a mounting mechanism for mounting the load port to the semiconductor manufacturing apparatus.
2. Related Background Art
In a manufacture process that needs a high level clean circumstance, such as a recent semiconductor device manufacture, an approach so called a mini-environment or a local clean space has been made in which a whole factory is not kept clean but only the environmental circumference for the products is kept clean. In brief, the interiors of the respective devices in the process are only kept clean, and the transfer and storing of the products to be processed between the respective devices (clean devices) are performed by using a container (clean box or pod) whose interior is kept clean.
In the case where an article to be transferred such as a semiconductor wafer within a pod is transferred to the clean device such as a semiconductor wafer processing apparatus (that is, loaded), an additional device called a load port is used. This load port is a device to be mounted detachably to the clean device and normally has a mechanism for automatically opening a lid of the pod and a table on which the pod is to be laid. Since the load port serves to open the lid of the pod, it is sometimes called an opener. The load port makes it possible to open the pod to the clean space of the clean device while keeping the sealed condition to the outside and transfer the article to be transferred (semiconductor wafer or the like) within the pod to the inside of the clean device.
If repairs are performed during the breakdown of the load port, they take a long period of time for suspension of the manufacture process, and the efficiency is low. Accordingly, the load port is formed as a discrete unit that may be detachably mounted on the clean device in order to make it possible to exchange the load ports per se in the breakdown. Recently, in the semiconductor manufacture apparatus field, the standards have been established for the load ports for the wafer having a diameter of 300 mm and an interface of the semiconductor apparatus.
When the conventional load port is mounted on the clean device, the load port is laid on a lifter and transferred close to the clean device, a positioning pin provided in the clean device is finely adjusted and fitted by the operator by using an alignment mechanism having a positioning cam or the like, and a plurality of bolts are fastened.
In the above-described conventional load port, it takes a long period of time to adjust the positions of the clean device and the load port. Also, a tool is required to fasten the bolts. The work is troublesome. In a conventional typical example, it takes about one hour to remove and mount the load port. Since the manufacture process is stopped during this work, it is demanded to shorten the time for the replacement.
Also, since the fixture is performed by using the bolts, the conventional method suffers from a disadvantage that the bolts may be lost during the replacement work.
In view of the above-noted defects, an object of the present invention is to provide a load port that may be replaced for a short period of time or a mounting structure for the load port.